Requirements

You cannot use your phone to spectate matches as it does not have the LoL client.

You cannot use firefox to download this file. So, please use Google Chrome or modify the name of the file yourself.

When Internet Explorer says the file may be harmful to your computer,

If you are using either Internet Explorer or Google Chrome, you will automatically receive a message as a result of downloading a ".bat" file. This file does not contain any virus or malware and can be executed safely by following the step-by-step instructions provided below.

If you are using Google Chrome, click the arrow on the right side in order to download

When using Internet Explorer, press the 'Advance' button to continue downloading.

If you are using Internet Explorer on Windows 8, click on Additional Information to run it.

When you receive a bug splat error

There is a problem with the LoL client. Please reinstall.

League of legend.exe file can not be found.

Right click on the LoL shortcut, then click on properties.

Copy the Starting Position of the shortcut tab.

Paste by pressing button.

When an error "failed to create dump file : (error3)" occurs while starting to specate.

Right click on the LoL shortcut, then click on properties.

After completely uninstalling LOL, reinstall it.

A hard, complicated way (Can solve quickly)

It goes to the folder where LOL is installed.

Find a folder called rads in the folder where LOL is installed, then capitalize the folder to RADS. If the folder's name doesn't change properly, first, change it to RADS_, then change it to RADS.